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 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
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package org.omg.PortableServer;

import org.omg.CORBA.ORB;
import org.omg.PortableServer.portable.Delegate;

/**
 * Defines the native <code>Servant</code> type. In Java, the
 * <code>Servant</code> type is mapped to the Java
 * <code>org.omg.PortableServer.Servant</code> class.
 * It serves as the base class for all POA servant
 * implementations and provides a number of methods that may
 * be invoked by the application programmer, as well as methods
 * which are invoked by the POA itself and may be overridden by
 * the user to control aspects of servant behavior.
 * Based on IDL to Java spec. (CORBA V2.3.1) ptc/00-01-08.pdf.
 */

abstract public class Servant {

  private transient Delegate _delegate = null;

  /**
   * Gets the ORB vendor-specific implementation of
   * <code>PortableServer::Servant</code>.
   *
   * @return <code>_delegate</code> the ORB vendor-specific implementation of
   * <code>PortableServer::Servant</code>.
   */
  final public Delegate _get_delegate() {
    if (_delegate == null) {
      throw
          new
              org.omg.CORBA.BAD_INV_ORDER
              ("The Servant has not been associated with an ORB instance");
    }
    return _delegate;
  }

  /**
   * Supports the Java ORB portability
   * interfaces by providing a method for classes that support
   * ORB portability through delegation to set their delegate.
   *
   * @param delegate ORB vendor-specific implementation of the <code>PortableServer::Servant</code>.
   */
  final public void _set_delegate(Delegate delegate) {
    _delegate = delegate;
  }

  /**
   * Allows the servant to obtain the object reference for
   * the target CORBA object it is incarnating for that request.
   *
   * @return <code>this_object</code> <code>Object</code> reference associated with the request.
   */
  final public org.omg.CORBA.Object _this_object() {
    return _get_delegate().this_object(this);
  }

  /**
   * Allows the servant to obtain the object reference for
   * the target CORBA Object it is incarnating for that request.
   *
   * @param orb ORB with which the servant is associated.
   * @return <code>_this_object</code> reference associated with the request.
   */
  final public org.omg.CORBA.Object _this_object(ORB orb) {
    try {
      ((org.omg.CORBA_2_3.ORB) orb).set_delegate(this);
    } catch (ClassCastException e) {
      throw
          new
              org.omg.CORBA.BAD_PARAM
              ("POA Servant requires an instance of org.omg.CORBA_2_3.ORB");
    }
    return _this_object();
  }

  /**
   * Returns the instance of the ORB
   * currently associated with the <code>Servant</code> (convenience method).
   *
   * @return <code>orb</code> the instance of the ORB currently associated with the
   * <code>Servant</code>.
   */
  final public ORB _orb() {
    return _get_delegate().orb(this);
  }

  /**
   * Allows easy execution of common methods, equivalent to
   * <code>PortableServer::Current:get_POA</code>.
   *
   * @return <code>poa</code> POA associated with the servant.
   */
  final public POA _poa() {
    return _get_delegate().poa(this);
  }

  /**
   * Allows easy execution of
   * common methods, equivalent
   * to calling <code>PortableServer::Current::get_object_id</code>.
   *
   * @return <code>object_id</code> the <code>Object</code> ID associated with this servant.
   */
  final public byte[] _object_id() {
    return _get_delegate().object_id(this);
  }

  /**
   * Returns the
   * root POA from the ORB instance associated with the servant.
   * Subclasses may override this method to return a different POA.
   *
   * @return <code>default_POA</code> the POA associated with the <code>Servant</code>.
   */
  public POA _default_POA() {
    return _get_delegate().default_POA(this);
  }

  /**
   * Checks to see if the specified <code>repository_id</code> is present
   * on the list returned by <code>_all_interfaces()</code> or is the
   * <code>repository_id</code> for the generic CORBA Object.
   *
   * @param repository_id the <code>repository_id</code> to be checked in the repository list or
   * against the id of generic CORBA objects.
   * @return <code>is_a</code> boolean indicating whether the specified <code>repository_id</code>
   * is in the repository list or is same as a generic CORBA object.
   */
  public boolean _is_a(String repository_id) {
    return _get_delegate().is_a(this, repository_id);
  }

  /**
   * Checks for the existence of an
   * <code>Object</code>.
   * The <code>Servant</code> provides a default implementation of
   * <code>_non_existent()</code> that can be overridden by derived servants.
   *
   * @return <code>non_existent</code> <code>true</code> if that object does not exist,
   * <code>false</code> otherwise.
   */
  public boolean _non_existent() {
    return _get_delegate().non_existent(this);
  }

  // Ken and Simon will ask about editorial changes
  // needed in IDL to Java mapping to the following
  // signature.
  /**
   * Returns an object in the Interface Repository
   * which provides type information that may be useful to a program.
   * <code>Servant</code> provides a default implementation of
   * <code>_get_interface()</code>
   * that can be overridden by derived servants if the default
   * behavior is not adequate.
   * @return <code>get_interface</code> type information that corresponds to this servant.
   */
    /*
    public org.omg.CORBA.Object _get_interface() {
        return _get_delegate().get_interface(this);
    }
    */

  // _get_interface_def() replaces the _get_interface() method

  /**
   * Returns an <code>InterfaceDef</code> object as a
   * <code>CORBA::Object</code> that defines the runtime type of the
   * <code>CORBA::Object</code> implemented by the <code>Servant</code>.
   * The invoker of <code>_get_interface_def</code>
   * must narrow the result to an <code>InterfaceDef</code> in order
   * to use it.
   * <P>This default implementation of <code>_get_interface_def()</code>
   * can be overridden
   * by derived servants if the default behavior is not adequate.
   * As defined in the CORBA 2.3.1 specification, section 11.3.1, the
   * default behavior of <code>_get_interface_def()</code> is to use
   * the most derived
   * interface of a static servant or the most derived interface retrieved
   * from a dynamic servant to obtain the <code>InterfaceDef</code>.
   * This behavior must
   * be supported by the <code>Delegate</code> that implements the
   * <code>Servant</code>.
   *
   * @return <code>get_interface_def</code> an <code>InterfaceDef</code> object as a
   * <code>CORBA::Object</code> that defines the runtime type of the <code>CORBA::Object</code>
   * implemented by the <code>Servant</code>.
   */
  public org.omg.CORBA.Object _get_interface_def() {
    // First try to call the delegate implementation class's
    // "Object get_interface_def(..)" method (will work for ORBs
    // whose delegates implement this method).
    // Else call the delegate implementation class's
    // "InterfaceDef get_interface(..)" method using reflection
    // (will work for ORBs that were built using an older version
    // of the Delegate interface with a get_interface method
    // but not a get_interface_def method).

    org.omg.PortableServer.portable.Delegate delegate = _get_delegate();
    try {
      // If the ORB's delegate class does not implement
      // "Object get_interface_def(..)", this will throw
      // an AbstractMethodError.
      return delegate.get_interface_def(this);
    } catch (AbstractMethodError aex) {
      // Call "InterfaceDef get_interface(..)" method using reflection.
      try {
        Class[] argc = {org.omg.PortableServer.Servant.class};
        java.lang.reflect.Method meth =
            delegate.getClass().getMethod("get_interface", argc);
        Object[] argx = {this};
        return (org.omg.CORBA.Object) meth.invoke(delegate, argx);
      } catch (java.lang.reflect.InvocationTargetException exs) {
        Throwable t = exs.getTargetException();
        if (t instanceof Error) {
          throw (Error) t;
        } else if (t instanceof RuntimeException) {
          throw (RuntimeException) t;
        } else {
          throw new org.omg.CORBA.NO_IMPLEMENT();
        }
      } catch (RuntimeException rex) {
        throw rex;
      } catch (Exception exr) {
        throw new org.omg.CORBA.NO_IMPLEMENT();
      }
    }
  }

  // methods for which the user must provide an
  // implementation

  /**
   * Used by the ORB to obtain complete type
   * information from the servant.
   *
   * @param poa POA with which the servant is associated.
   * @param objectId is the id corresponding to the object associated with this servant.
   * @return list of type information for the object.
   */
  abstract public String[] _all_interfaces(POA poa, byte[] objectId);
}
